ORTHODONTIC DEVICE

CROSS REFERENCE TO RELATED APPLICATIONS This application claims benefit as a continuation-in-part of U.S. Provisional

Application No. 60/976,425, filed September 29, 2007, and U.S. Provisional Application No. 60/976,423, filed September 29, 2007 the entire contents of which are hereby incorporated by reference herein in its entirety for all purposes.

FIELD OF THE INVENTION The present disclosure relates to a removable orthodontic device.

BACKGROUND OF THE INVENTION

Biomechanical loading is thought to be an important regulator of osteogenesis, as bone formation occurs in response to its functional environment. Based on this information, biophysical techniques of osteo-stimulation have been successfully introduced into clinical practice.

These biophysical techniques include craniofacial distraction osteogenesis, and the application of ultrasound etc. to promote bone formation. As well, titanium implants are commonly used in orthopedics and dentistry. These implants integrate into the host's bone by a complex process known as osseo-integration. Data suggest that micromechanical forces may have anabolic effects on bone in-growth surrounding intra-osseous titanium implants.

For example, micromechanical forces of 20OmN at IHz axially have been delivered to implants for 10 min/day for 12 consecutive days. The average bone volume near the mechanically loaded implants was significantly greater than the unloaded control side, and the average number of bone -producing osteoblast-like cells was significantly greater on the loaded side compared to the controls. There was also a significant increase in mineral apposition and bone-formation rate for the mechanically stressed implants compared to the controls. Therefore, modulation of bone in-growth can occur by in vivo micromechanical loading.

A considerable part of oral and maxillofacial surgery deals with bone healing. Recently, low-intensity ultrasound treatment has been shown to reduce the healing time of

bone fractures. To observe the clinical effects of low intensity ultrasound after tooth extraction in patients, the sockets on one side were treated with low intensity ultrasound while the other side underwent no treatment. It was found that clinical use of low intensity ultrasound reduced post-operative pain and the incidence dry socket, and it also stimulated bone healing after extraction of mandibular third molar teeth. Therefore, the potential of ultrasound to stimulate maxillofacial bone healing may be of value in other orthopedic applications.

One study applied ultrasound to human gingival fibroblasts, mandibular osteoblasts, and monocytes. Ultrasound was found to induce cell proliferation in fibroblasts and osteoblasts by 35-50%. Collagen synthesis was also significantly enhanced (up to 110%) using a 45 kHz ultrasound device with intensities of 15 and 30mW/cm (SA). In addition, angiogenesis -related cytokine production, such as IL-8, bFGF and VEGF were also significantly stimulated in osteoblasts. Therefore, therapeutic ultrasound induces in vitro cell proliferation, collagen production, bone formation, and angiogenesis. Sutures are fibrous connective tissue articulations found between intramembranous craniofacial bones. They consist of multiple connective tissue cell lines such as mesenchymal cells, fibroblasts, osteogenic cells and osteoclasts. Sutures are organized with osteogenic cells at the periphery, producing a matrix that is mineralized during bone growth and development; with fibroblastic cells with their matrices in the center. Cyclic loading of these sutures may have clinical implications, acting as mechanical stimuli for modulating craniofacial growth and development in patients. One study demonstrated that in vivo mechanical forces regulate sutural growth responses in rats. In that study, cyclic compressive forces of 30OmN at 4Hz were applied to the maxilla for 20 min/day over 5 consecutive days. Computerized analysis revealed that cyclic loading significantly increased the average widths of the sutures studied in comparison with matched controls, and the amount of osteoblast- occupied sutural bone surface was significantly greater in cyclically loaded sutures. These data demonstrate that cyclic forces are potent stimuli for modulating postnatal sutural development, potentially by stimulating both bone formation (osteogenesis) and remodeling (osteoclastogenesis). In a similar study, static and cyclic forces with the same magnitude of 5N were applied to the maxilla in growing rabbits in vivo. Bone strain recordings showed that the waveforms of static force and IHz cyclic force were expressed as corresponding static and

cyclic sutural strain patterns. However, on application of repetitive 5N cyclic and static forces in vivo for 10 minutes/day over 12 days, cyclic loading induced significantly greater sutural widths than controls and static loading. Cell counting also revealed significantly more sutural cells on repetitive cyclic loading than sham control and static loading. Fluorescent labeling of newly formed sutural bone demonstrated more osteogenesis on cyclic loading in comparison with sham control and static loading. Thus, the oscillatory component of cyclic force, or more precisely the resulting cyclic strain experienced in sutures, is a potent stimulus for sutural growth. The increased sutural growth by cyclic mechanical strain suggests that both microscale tension and compression induce anabolic sutural growth response. Therefore, mechanical forces readily modulate bone growth, and cyclic forces evoke greater anabolic responses of craniofacial sutures and cartilage.

In another study, the premaxillo-maxillary sutures of growing rabbits received in vivo exogenous static forces with peak magnitudes of 2N, or cyclic forces of 2N with frequencies of 0.2Hz and IHz. The static force and two cyclic forces did not evoke significant differences in the peak magnitude of static bone strain. However, cyclic forces at 0.2Hz delivered to the premaxillo-maxillary suture for 10 min/d over 12 days (120 cycles per day) induced significantly more craniofacial growth, marked sutural separation, and islands of newly formed bone, in comparison with both sham controls and static force of matching peak magnitude. These data demonstrate that application of brief doses of cyclic forces induces sutural osteogenesis more effectively than static forces with matching peak magnitude. Sutural growth is accelerated upon small doses of oscillatory strain (600 cycles delivered 10 min/day over 12 days), and both oscillatory tensile and compressive strains induce anabolic sutural responses beyond natural growth. Therefore, oscillatory strain likely modulates genes and transcription factors that activate cellular developmental pathways via mechanotransduction pathways. Thus, sutural growth is determined by hereditary and mechanical signals via gene- environmental interactions or epigenetics. Therefore, small doses of oscillatory mechanical stimuli have the potential to modulate sutural growth for therapeutic objectives.

The above data suggest that orofacial sutures have capacities for mechanical deformation. The elastic properties of sutures are potentially useful for improving our understanding of their roles in facial development. Current data on suture mechanics suggest

that mechanical forces regulate sutural growth by inducing sutural mechanical strain. Therefore, various orthopedic therapies, including orthodontic functional appliances, may induce sutural strain, leading to modification of natural sutural growth.

Singh et al. reported dental and facial changes in adults treated with a static removable orthodontic appliance (US patent application # 20050260534). The maxillary arch showed a 30% relative size increase in the mid-palatal region (corresponding to the mid- palatal suture) with shape changes consistent with improved dental alignment and maxillary expansion in the transverse direction. However, the treatment time was excessively long (up to 30 months in one case). Nevertheless, current orthodontic and dentofacial orthopedic therapies exclusively utilize static forces to change the shape of craniofacial bones via mechanically induced bone apposition and resorption, but cyclic forces capable of inducing different sutural strain wave forms may accelerate sutural anabolic or catabolic responses.

Recently, it was shown that low intensity pulsed ultrasound enhances jaw growth in primates when combined with a mandibular appliance, and that orthodontic ally induced root resorption can be repaired using ultrasound in humans. Therefore, the development of a removable orthopedic-orthodontic appliance with cyclic functionality is warranted, as cyclic forces more effectively stimulate sutural osteogenesis than static forces, and a system and method to bioengineer vibrational orthopedic-orthodontic devices is described here.

Additionally, conventional orthodontic therapy is based on the premise that when a force is applied to a tooth, the tooth will move in response to the force. Thus, conventional fixed orthodontic approaches are primarily based upon the manipulation of teeth by exerting, controlling and maintaining forces, vectors and moments on teeth and/or roots. This torque control can be exerted on teeth either individually, segmentally or by the use of wires that engage the entire dental arch through the use of brackets. In order to apply corrective forces, sophisticated systems of brackets and wires are commonly deployed. Brackets and/or bands of various designs are directly bonded to the surfaces of the teeth. The brackets have slots at various orientations that can engage wires. The wires are also of different materials, such as stainless steel and/or other alloys such as Nickel-Titanium; and of different cross-sectional shapes, such as round, square or rectangular; and of different sizes e.g. 0.016 inch round and 0.018 by 0.022 inch rectangular etc.

The wires are ligated to the brackets in various ways to permit low-friction, sliding mechanics, for example. Typically, the first phase of this biomechanical orthodontic correction is leveling using round wires, followed by more detailed tooth re-orientation using rectangular or square wires. Other corrections, such as space closure, are often accomplished by using elastics attached to the brackets or coil springs along the arch-wire to pull or push teeth into positions as determined by the orthodontic clinician.

From the patients' viewpoint, apart from esthetic considerations, one of the drawbacks of conventional fixed appliances is the trauma that the metallic orthodontic components and/or elastics may cause. The inside surface mucosa of the cheeks and lips, as well as the tongue, routinely contacts the metallic orthodontic components and/or elastics during swallowing speech and mastication, which can cause cheek-biting, painful mouth ulcers, etc. In addition, inappropriate forces and moments that reach or exceed physiologic blood pressure during fixed orthodontic treatment can cause root resorption, by producing stresses in the periodontium. To avoid high pressures, the acting forces on each tooth need to remain below about 0.5N. These levels of forces can be achieved by using Nickel-Titanium (NiTi) wires with a diameter of 0.012 inch, for example. The use of NiTi wires ensures an almost constant moment (torque) based on its stiffness, spring-back, shape memory, and elasticity.

A superior NiTi alloy wire has been developed by the Furukawa Electric Co., Ltd., Japan. This Japanese NiTi wire exhibits "super-elasticity" in that this particular wire delivers a constant force over an extended portion of its deactivation range. This Japanese NiTi alloy wire undergoes minimal permanent deformation during activation, and its stress remains nearly constant despite the change in strain within a specific range. This unique feature is called 'super-elasticity'. Moreover, Titanium- Niobium- Aluminum (Ti-Nb-Al) springs generate lighter and more continuous forces. Thus, Ti-Nb-Al wire has superior mechanical properties for smooth, continuous tooth movement, and Ti-Nb-Al wire may be used as a nickel-free, shape-memory and super-elastic alloy wire for orthodontic tooth movement instead of Ni-Ti wire.

Similarly, NiTi coil springs, used with elastic chains, can generate nearly constant forces over a wide range of activation due to low load deflection. Reducing the load deflection rates of orthodontic springs is important, as it provides relative constancy of the moment-to-force ratio applied to the teeth with concomitant, predictable tooth movements.

Lower load deflection rate springs increase patient comfort and reduce the number of office visits, while lowering potential tissue damage.

Using 0.016" x 0.022" NiTi and multi-stranded arch wires employed in a 0.018" slot system, with power-hooks or up-righting springs, bodily tooth movements can be achieved. But, friction may increase if the up-righting torque is too strong and other unwanted side effects such as tooth extrusion, rotation and tipping can also occur. Therefore, the load- deflection rate of an orthodontic spring depends on the modulus of elasticity of the utilized alloy and the geometric configuration of the spring. Thus, it is usually preferable to choose springs with a low load-deflection rate of about 50 p/mm (50kN/mm ² ). Nevertheless, it has been found that the force systems produced by straight wire and conventional up-righting springs can show severe extrusive force components, which may lead to occlusal trauma. Furthermore, intra-oral adjustment of up-righting springs is difficult because of high susceptibility to minor modifications of geometry.

Prior art had described the design and construction of the stainless steel flap springs utilized including springs constructed of heat-treated alloy wire transversely orientated against the palatal/lingual surfaces of the pertinent teeth. Nevertheless, palatal finger springs; open springs; boxed springs; cranked palatal springs; re-curved springs, double cantilever or

Z-springs, and T-springs etc. that are transversely orientated against the palatal/lingual or mesial/distal surfaces of the pertinent teeth are commonly found in the orthodontic literature as known by those skilled in the art. Indeed, the use of acrylic buttons attached to the palatal/lingual surfaces of pertinent teeth has been commonly deployed to prevent the transversely orientated spring from riding up the palatal/lingual tooth surface.

SUMMARY OF THE INVENTION

Disclosed is a removable orthodontic appliance. The orthodontic appliance provides a means for delivery of an intermittent vibrational signal to the periodontium and/or craniofacial sutures to induce a response from the patient's genome in order to remodel hard and soft tissues. These vibratory signals stimulate mechanoreceptors within the periodontium which invoke a genomic response which in turn grows new bone and remodels bone. The appliance presented stimulates the production of new bone at the sutural level via vibratory signals rather than overwhelming force as is presently used in conventional orthodontics.

In this disclosure, the term "comprising" means including the elements or steps that are identified following that term, but any such elements or steps are not exhaustive, and an embodiment may include other elements or steps.

In its simplest form, the orthodontic appliance comprises at least one arch; either a maxillary portion or a mandibular portion. In a more preferred embodiment, the orthodontic appliance comprises both maxillary and mandibular portions; preferably not connected to one another. Each portion comprises at least two adjoining substrate sections or halves that are displaceable relative to one another and made of a hard material typically used in orthodontics, preferably acrylic and configured for proper engagement to a patient's oral structure.

An intermittent vibrational signal means is used for delivery of an intermittent vibrational signal to the periodontium. As used herein, an intermittent vibrational signal is defined to mean vibrational, oscillatory or ultrasonic. In its simplest form, the intermittent vibrational signal means comprises a plurality of tooth contacting components having their ends secured or anchored to a respective substrate section. More preferably, each tooth contacting component is in contact with a single tooth.

Each tooth contacting component rests against the inside labial surface and projects only a slight or de minimus force upon the surface to ensure the component is contacting the surface for efficient transmission of the vibrational signal. By definition, a slight or de minimus force means a lesser force than what is used by orthodontists for tooth realignment using braces.

In a preferred embodiment, the tooth contacting components are preferably preformed axial springs adapted for contacting the tooth along the long axis of the palatal/lingual surfaces. The tooth contacting components can be adjusted as required by a clinician and require no more than the force necessary to maintain engagement of the appliance to the patient and tooth contacting components contacting respective teeth. Preferably, no more than 50 grams force/sq.cm of root enface would be required and most preferably no more than 20 grams force/sq.cm.

An important feature of the invention is the ability to impart an intermittent vibrational signal means via contact with the teeth to the periodontium. A user of the orthodontic appliance described herein will not have to endure the discomfort associated with

conventional orthodontic appliances since the force applied to each tooth is not for forceful tooth displacement but rather to simply convey a vibrational signal.

Another important feature of the invention is that the tooth contacting components efficiently deliver a desired vibrational effect to the targeted respective tooth. Preferred tooth contacting components may take the configuration of an orthodontic spring and depending upon the spring configuration, may require a material of choice other than the more conventionally used stainless steel. Any wire able to convey sufficient vibration to the tooth is envisioned by this invention. However, for the axial spring design disclosed in a preferred embodiment, where each tooth contacting component is made into an axial spring form where the wire is configured back and forth in a transverse direction across the tooth to provide an appreciable surface contact between the spring and the lingual surface of the tooth, a wire material with a stiffness less than stainless steel is required.

Preferably, a β-titanium orthodontic wire is used for the axial spring construction. Orthodontic wires made from β-titanium have a degree of stiffness sufficiently less than that of stainless steel. In the most preferred embodiment, the β-titanium orthodontic wire used has a 0.38% stiffness to that of stainless steel and is sold under the trademark RESOLVE®, GAC International, Inc., Islip, NY. A wire with less stiff properties allows the wire to more easily bend into the desired shape without losing its vibrational properties.

Preferably, wire diameter is between 0.012 and 0.018 inch, the width of the spring in the transverse plane will be about 5mm for the lower front teeth, about 6mm for the upper front teeth and about 8mm for the upper and lower molars. The radius of the bends is approx lmm and the overall length of the finished spring is about 10mm.

Typically, both the maxillary and mandibular portions are operatively attached to the teeth with clasps, bands or direct bonding to the surfaces of the teeth with orthodontic brackets. A labial bow and other wires in the form of springs can also be provided as required. The body of the device lies in close approximation to the palate in the maxillary portion; and on the lingual areas in the mandibular portion.

In one embodiment, extensions of the substrate symmetrically overlay the biting

(occlusal) surfaces of at least two of the patient' s teeth in the space where those teeth would normally contact the opposing teeth from the upper or lower jaw. The thickness of the occlusal coverage ranges from approximately 0.5 mm to approximately 5.0 mm, as

determined by orthodontic equilibration, and may be absent in certain locations or spots, if required. The plate body itself has a thickness that varies, and ranges from about 1.0 mm to about 5.0 mm, depending upon the components substantially encapsulated within it. In another embodiment, overlays may not be required for a particular patient. To induce changes in the form of the jaw and/or facial bones, as well as the positions of teeth, the device is operatively positioned so the upper and lower posterior teeth do not contact one another. This lack of biting contact, especially of the posterior (back) teeth enhances the effect of cyclic, intermittent forces applied via the substrates and through individual wires formed as springs that contact the teeth. The vibration delivered by the plurality of tooth contacting components to the teeth stimulate the patient's jaw (alveolar) and facial bone genes while wearing the device. The vibration of the periodontium engages mechano-receptors within the periodontium which in turn sends signals to the patient's genome to induce osteogenic and osteoclastogenic remodeling. In the manual version, the vibration signal is delivered by intermittent contact of maxillary and mandibular arches with one another or one of the arches against teeth. In an electronic version by a micro or meso motor powered by a power source such as a battery conveys the vibrational signal to the periodontium via the teeth.

In the manual version, the intermittent maxillary and mandibular contact of the substrates is estimated to be for about 20-30 minutes per day and/or while sleeping at night through normal intermittent contact such as during mastication or swallowing. This frequent, cyclic, intermittent signaling of the facial and alveolar bones causes development of the facial and jaw bones that did not occur optimally during childhood. This bone development may include remodeling of the palate, eruption of the teeth, remodeling of the facial bones and jaws etc., according to the patient's genome. It should be noted that the teeth are expected to relocate outwards; in effect the jawbone will be expanded to accommodate the new positions of the teeth, without any new spacing occurring between individual teeth.

The manual version relies upon the premise that over the course of wearing the device, a person will intermittently close their jaw. As the jaw closes, the maxillary and mandibular portions will contact one another. This contact will generate a vibration signal which will then be communicated across the lingual surface of each tooth in contact with a respective

orthodontic spring specially designed for effectively conveying the signal. A manual actuator, well known in the prior art, is used for periodic spacing adjustment of the adjoining sections from one another. The purpose for displacing the adjoining sections of a maxillary or mandibular portion is for maintaining a consistent level of intimate contact upon the tongue side surface of the teeth.

It is to be noted that the purpose of the tooth contacting components is not to impart a force upon the tooth so as to force it in a particular direction, but rather to deliver a vibrational signal to the periodontium.

Spring Design and Application The tooth contacting components are preferably orthodontic springs which can be constructed to not only cover a substantial area of the tooth surface by having the wire configured in a back and forth pattern in the transverse plane, but to also permit each axial spring to be adjusted in the axial plane superiorly or inferiorly as desired by the clinician. This is made possible by the wire configured in the perpendicular direction relative to the tooth surface. In other words, the pattern of this segment can be changed or adjusted to lengthen or shorten the axial length which the pattern of the wire in the transverse plane remains the same; thus providing the same tooth surface contact area.

The springs necessary for conveying the vibratory signal to the teeth will be orientated to be substantially parallel and contacting the lingual surface along the long axis of a respective tooth. In other words, the spring is orientated axially to the lingual surface from near the mucosa but not extend over the incisal edge of the tooth while another portion of the spring forms a pattern in the perpendicular direction behind the spring portion contacting the tooth surface.

Teeth are responsive to axial stimuli preferentially through physiologic mechanisms. These developmental mechanisms include active tooth eruption, passive tooth eruption; and the tooth support phenomenon.

For example, when a deciduous tooth is lost, the permanent tooth will typically actively erupt in an axial direction until it makes contact with an opposing tooth or teeth. Similarly, when a tooth is extracted, the tooth on the opposing jaw structure can passively erupt until it meets some hindrance.

Teeth are genetically programmed for axial movement. A tooth will undergo elastic intrusion when an axial force is applied. When the axial force is removed, the tooth undergoes elastic extrusion so that the tooth returns to its original position, in balance or in equilibrium with the opposing tooth/teeth. However, when an orthodontic device is applied to a tooth, these natural mechanisms of homeostasis can be overpowered.

In contrast, during the development of the dentition, commonly referred to as tooth eruption, it is now thought that inherited genes are transcribed and expressed. The timing and orderly eruption of teeth is genetically-encoded in a developmental mechanism that is part of a systemic phenomenon called temporo-spatial patterning. In other words, specific teeth develop at specific sites at specific times. Thus, there is an innate, physiologic mechanism of tooth alignment that can be overpowered by biomechanical orthodontic therapy.

Moreover, current research in molecular genetics suggests that external stimuli can cause the expression of genes that are not normally expressed. Therefore, the application of appropriate external stimuli to teeth that have already completed their eruptive phase can cause these teeth to take up new positions in accord with the patient's genetics as determined by temporo-spatial patterning.

Bearing in mind that teeth are adept at adapting to stimuli in the axial direction, the spring design described herein is substantially parallel to the long axis of the lingual surface of the tooth, unlike all previous designs that contact the lingual surface of the tooth in the transverse plane.

The spring design disclosed attempts to provide as much contact with the lingual surface as possible in order to convey an intermittent vibrational signal to the periodontium. This is accomplished by the spring configured in a back-and-forth design in the transverse plane to substantially contact the tooth from the mesial to the distal side without imparting a substantial force as is typical in conventional bio-mechanical orthodontics. Again, the purpose of the spring design is to maximize the transmission of an intermittent vibratory or ultrasonic signal via the tooth to the periodontium and further allow positional adjustments by the clinician to transmit a signal to a preferred side of the tooth.

Electronic version For the electronic version, the intermittent vibrational signal means comprises the same tooth contacting components as described for the manual version, an electronic means

for adjusting the adjoining substrate sections for maintaining a consistent level of intimate contact upon the tongue side surface of the teeth, comprising pressure sensors, micro-motors, an actuator and microprocessor operatively connected to one another as will be described in detail later. In the electronic version, the intermittent vibrational signal means can be delivered as vibration, ultra-sonic or oscillation.

Electrical ultrasonic/vibrational, meso-motors or micro-motors can be substantially encapsulated and operatively connected to one another within respective sections of each substrate. The signals generated by these motors can be altered as desired by the clinician and varied either manually or through the use of a microprocessor, chip or programmable integrated circuit which would also be embedded. In one embodiment, the motors would be substantially encased within a vibration dampening material and connected to each tooth contacting component so that essentially most of the vibratory signal would be delivered to the tooth contacting components rather than to the substrate sections as a whole.

In addition, these small electrical motors can also be utilized to adjust the separation of respectively adjoined substrate sections automatically through the use of pressure sensors in contact with several tooth surfaces to ensure the device remains in contact with the tissues without having to manually adjust the appliance. These sensors can be used to monitor, download and measure the pressure applied to each tooth or groups of teeth. Alternatively, the sensors can be located in other positions, such as the substrate to record readings in the roof of the mouth or floor of the mouth, and to provide soft tissue pressure measurements.

In addition, by developing a three dimensional spatial chart for each patient using a CAT scan, subsequent changes to tooth position and other structures can be monitored, downloaded and measured for calculations and predictive modeling of changes using appropriate computer software. Any adjustments deemed necessary by the clinician can be made by applying an electric current to the micro-or meso-motors, assisted by the readings of the output of the sensors and/or the global positioning system. For these reasons, a microprocessor is preferably included as part of the electronic version.

In order to power the microprocessor, a battery or other suitable power supply will be operatively connected within a respective portion. The battery is similar to those used for hearing aids or bone conductors. The microprocessor is supplied via conducting wires with

information from the pressure sensors, and its output can drive the ultrasonic/vibrational, micro-motors or meso-motors, operatively connected to the tooth contacting components, in order to deliver the desired vibrational signal to the lingual surface of the teeth.

Micromechanical, cyclic, tensile and/or compressive forces and/or doses of oscillatory strain will be applied using an ultrasonic/vibrational component similar to that found in ultrasonic dental sealers, electric toothbrushes, ultrasonic dental cleaning appliances and cellular telephones. The range of force applied will be very low and vary between 0.1-lON although forces of other magnitudes may be applied as required. The frequency applied will vary between 1-600Hz although other ranges of cycles may be applied as required. The device can be activated for 10-60 minutes per day although other durations of application may be used as required.

The device may be used in conjunction with conventional fixed orthodontic appliances (braces), if required. It may also be used as a component in a two-phase orthopedic-orthodontic treatment. The device should be equally applicable to child, teenage and adult dental patients.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a patient's oral cavity with a maxillary portion of the orthodontic appliance in position.

FIG. 2 is a view of the spring configuration taken along view 2 of FIG. 1. FIG. 3 is a view of FIG. 2 taken along line 3-3.

FIG. 4 is a view of the maxillary portion in an electronic version.

FIG. 5 is a perspective view of one embodiment of an axial spring.

BEST MODE FOR CARRYING OUT THE INVENTION

Fig. 1 illustrates an orthodontic appliance 10 comprising a maxillary portion 12, clasps 13 and a labial bow 14. Maxillary portion 12 is made from acrylic and further comprises substrate halves 16 and 18 which are operatively connected to each other by an actuator 20 which can displace the halves from one another for maintaining portion 12

contact with a patient's upper set of teeth. A lower mandibular portion 11 having clasps 13 and labial bow 14 is also illustrated and may be used if the clinician deems necessary.

Fig. 2 and Fig. 3 illustrate the pattern of a tooth contacting component which is an axial spring 22 against a respective tooth A. Fig. 5 illustrates a perspective view of spring 22. Spring 22 comprises two ends 24 and 26 which are embedded in the acrylic substrate. Spring 22 further comprises a midsection operatively positioned for contact with the lingual surface of at least one tooth. The mid-section comprises a first segment 28 and a second segment 30, where first segment 28 extends upward from the substrate in a back-and forth pattern in the transverse plane relative to the lingual surface of a tooth and the second segment 30 extends upward from said respective substrate section in a back-and forth pattern in a perpendicular plane relative to the lingual surface; and where the first and second sections join at near the incisal edge of a tooth to form a central arc 32.

Oral appliance 10 is appropriately sized for a patient's mouth by taking impressions well known in the prior art. Once positioned properly, spring 22 is in operative contact with the lingual surface of tooth A and does not impose any significant force for urging in a particular direction as is customarily done in conventional orthodontics. The operative contact mentioned above and during, for example, swallowing or mastication, will cause portions 11 and 12 to contact one another. This intermittent contact will create a vibration which will be transmitted through spring 22 to the periodontium P via a patient's respective tooth A.

The first segment 28 and second segment 30 have a plurality of undulating U-bends that comprise the body of axial spring 22. The plurality of U-bends may vary in amplitude, being bigger or smaller in size. The plurality of U-bends may vary in frequency, being many or few in number.

The plurality of U-bends may vary in characteristic, being differently shaped, such as a 'Z' formation or a square waveform etc. The plurality of U-bends in segments 28 and 30 lie in close approximation with respect to each other for the entire length of said active (compression-extension) axis of said axial spring. Axial spring 22 lies on the lingual surface of the contiguous oral structures (mucosa) substantially parallel to the long axis of the lingual surface of the tooth. The head of the axial spring intimately contacts the long axis of said palatal/lingual surface of the tooth. It should be noted that Fig. 3 shows a slight space between tooth A and spring 22. This is for

illustrating the proper structure of spring 22. In practice, spring 22 will be in contact with tooth A.

The spring-tooth relationship shown in Fig. 2 and Fig. 3 are repeated for any other teeth requiring treatment and incorporated into the design of both mandibular portion 11 and maxillary portion 12. In other words, additional tooth contacting components or axial springs

22 will be orientated substantially parallel to the long axis of the palatal/lingual surface of a respective tooth.

The axial spring is a three dimensional spring design wherein second segment 30 is orientated substantially parallel to the long axis of the lingual surface of the tooth, and first segment 28 is orientated approximately parallel to the transverse axis of said lingual surface of the crown of said tooth.

The U-bends of second segment 30 permit a clinician to adjust the length of overall spring 22. A space is present between second segment 30 and maxillary portion 12 to allow sufficient clearance for a clinician to axially adjust the length of spring 22. As mentioned earlier, if required by a clinician, oral appliance 10 can also include mandibular portion 11 having the features presented for maxillary portion 12. As is well known, mandibular portion 11 does not include a palatable substrate area as is formed as part of maxillary portion 12.

Additionally, an electronic version of an oral appliance, as shown in Fig. 4 would include a plurality of pressure sensors 40 operably connected to an actuator 20a, and microprocessor 42, mesomotor 44, and battery 46 which are embedded within a respective maxilliary portion 12 or mandibular portion 11. Microprocessor 42 would maintain the oral appliance against the oral teeth structure with a pre-determined force as measured by pressure sensors 40.

I claim: